When you incorrectly perform a donkey punch on a female and end up with an unconscious girl with an extremely tight butthole caused by her entire nervous system going into shock after you've incorrectly donkey punched her in the back of the head. The butthole may be so tight as to prevent removal, sucking the dick in deeper like quicksand.

"The other night I stuck my cock in a Dyson vacuum."
"Oh, like a Black Vortex?"